Towed implements are well known in numerous industries. Some implements include rear wheels to support the rear end of the implement while the front end of the implement is supported by the implement hitch resting on the drawbar of the towing vehicle. The implement hitch pivots with respect to the drawbar about a vertical axis provided by the drawpin, and this configuration allows tight turning of the implement and towing vehicle.
Where the towed implement is larger, the hitch or drawbar may not practically be designed to support the front end of the implement, and front wheels are provided to support the front end of the implement. These front wheels are typically caster wheels pivotally mounted about a vertical axis to facilitate turning the implement. Fixed wheels would be forced laterally and skid along the ground during turns causing considerable stress on the implement.
A problem with caster wheels is that they allow the implement to wander in some conditions, such as when working on a slope. Gravity will pull the front end down the slope, and the caster wheels simply follow and provide no counteracting force, so that the towed implement will pivot about the drawpin and the implement will move laterally, requiring the operator of the towing vehicle to make course corrections. Further, where the implement is for example a multi-blade rotary cut mower, when the mower skews instead of moving in a substantially aligned forward direction, proper overlap of the several blades on the mower may not be achieved and a strip of vegetation in the middle of the mower may be uncut.